Pay for it at iTunes store.
No need to cheat. When you clock the stars and keys for each stage, you will get coins in every game you play and every lawn mower you save.
I keep getting diamonds and gold coins, I already have more than 40K of coins.
If you have a tactic, hardly you will need to use the coins to do power-ups.
This game is like giving away for free IMHO.


The upgrade of additional plants need to buy with money, and no way to use earn coins to purchase. And dont know what is the use of the coins earn.
The plant food is bought by clicking the + next to the plant food bar.I mean at the store. Can't use coins to buy plants.
I mean at the store. Can't use coins to buy plants.